DESCRIPTION: (Applicant's Description) Lung cancer, the leading cancer cause of death in the United States, is known to be primarily caused by smoking tobacco products. Lung cancer in nonsmokers is thought to be primarily attributable to environmental tobacco smoke (ETS) and/or occupational exposures. Little is known, however, about the relative contribution of occupational sources of environmental toxins, in particular the contribution of workplace ETS, to the risk of lung cancer in nonsmokers. Interpretation of the existing evidence is further complicated by racial/socioeconomic differences in the workforce distribution and in the prevalence of active smoking in these groups. The proposed study is designed to evaluate the interrelationships between race, occupation and workplace ETS to risk of lung cancer in women who have never themselves smoked tobacco products. It builds upon a nearly decade long national collaborative multicenter case-control study of lung cancer in nonsmoking women, the largest study of its kind in the United States. The population-based study sample consists of two groups of lifetime nonsmokers; 653 women with newly diagnosed carcinomas of the lung, and 1,253 age and area matched population controls. Analyses are designed to estimated, via unconditional logistic regression, the approximate relative risks for lung cancer associated with employment in certain occupations/industries and with exposure to toxic agents in the workplace (especially ETS) independent of race, socioeconomic status, other sources of ETS exposure, and other putative risk factors for the disease. Data from these analyses can make an important contribution to concerns about workplace exposure contributions to risk of lung cancer.